


Thyne Bound, Darkest Dreaming

by BlueKittyKnitting



Category: Undertale (Video Game)
Genre: Anal Play, Breeding, Ecto-Genitalia (Undertale), Ecto-Penis (Undertale), Ecto-Tentacles (Undertale), Ecto-Tongue (Undertale), Ecto-Vagina (Undertale), F/M, Multi, Orgy, Other, Oviposition, Sex Toys, Vaginal Sex
Language: English
Status: Completed
Published: 2021-03-10
Updated: 2021-03-10
Packaged: 2021-03-16 18:15:27
Rating: Mature
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 2
Words: 3,867
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/29953956
Author URL: https://archiveofourown.org/users/BlueKittyKnitting/pseuds/BlueKittyKnitting
Summary: His mate was now his, as Blue was now Horror's. Nestled away in his domain, where he had all he wanted.Until Cross's appearance, leading to events upending his existence once again. Settling with this outcome unexpected. How truly interesting, such darkest dreams coming to fruition.
Relationships: Nightmare Gang & Sans (Undertale), Sans (Undertale)/Reader
Comments: 4
Kudos: 43





	1. One

**Author's Note:**

  * For [AcidGreenFlames](https://archiveofourown.org/users/AcidGreenFlames/gifts), [Alennyah](https://archiveofourown.org/users/Alennyah/gifts), [ChrysopraseCarnelian](https://archiveofourown.org/users/ChrysopraseCarnelian/gifts).
  * Inspired by [Finding A Safe Haven](https://archiveofourown.org/works/23795623) by [AcidGreenFlames](https://archiveofourown.org/users/AcidGreenFlames/pseuds/AcidGreenFlames). 



> The continuation to Dark Tidings. 
> 
> Some awesome and amazing friends inspired me on this.
> 
> Thank you for reading. :)

The sound of her breathless cries and the slapping of bone on skin echoed through the dim room.

Nightmare sitting back against the ornate mahagony headboard, reclined against a vast number of either plush or satin crimson and black pillows. Entirely naked, down to his dark bones. A grin on his face as he sipped at the glass of wine in his hand, body slightly more oily. Emitting a faint sheen from the light of the numerous candles set all over on most surfaces, illuminating the room in a particular glow.

Panting quietly, he had one of his tentacles wound around his cock, watching the delicious scene before him. On one end of the impossibly massive bed was his consort, his sweet mate. On her knees, skin slick with sweat and her highly mussed hair clung to her tantalizingly naked frame as Killer gripped one side of her waist, fucking her deep from behind.

His right hand skeleton mounted her, holding on to the handle of the leash with the other end attached to the soft dark collar around her neck. Watching with a heavy lidded expression, eye darkened with desire as she was taken by the mad skeleton. Bouncing along with his rhythm as she was held up from an angle that was comfortable. Seeing her rounded belly, the evidence of his seed having taken root and grown inside of her for the last five months.

She cried out loudly, incoherent as her unfocused eyes rolled up as Killer continued on. He was breathless, enjoying his treat. Growling quietly as his skull dropped back from the sheer sensation of her sheath wrapped tight around him. "fuck boss!" he hissed, chuckling quietly.

"she's so tight!" Nightmare grinned, glancing at her face to see her expression contorting in pleasure. "it feels so good! she feels like heaven!" it was good to see his usually emotionless subordinate enjoying himself.

"she certainly has the silken pussy..." Nightmare murmured. "would you be interested in the same?"

Killer laughed. "dunno! just love how she feels!"

Nightmare grinned more, glancing over towards the other side where Horror was sitting there on his knees. Large hands holding onto Blue's legs as he thrust hard inside of his pussy. Having the sweet little Sans on his back, as the once man eater was leaning over him. Slumped forward some, running a crimson tongue along his teeth as he enjoyed seeing his prey coming undone.

While Dust was also on his knees over by Blue’s skull, having tilted his head back and fucking his mouth with a fervor usually seen in battle. Groaning loudly, his hood thrown back and his eye lights fuzzed while giving in to the desire dragging through their bodies. Horror letting go to reach up, rubbing Blue's swollen belly of the souling growing inside of him.

An oddly sweet smile, a touch possessive. Eliciting a whimper from Blue as he was fucked between them, eye lights in the shape of sparkly hearts while Horror leaned more over him. Running his wet, long tongue over one of Blue's nipples and eliciting a muffled cry. Arching his back inciting Dust to go even faster, murmuring too quietly to understand. But it was clear he was growing close while Horror sucked hard on the teet.

While their main course was sitting there before him. Dream stripped down to his bones and golden ecto. A ball gag in his mouth to prevent him from speaking, his arms bound behind. Two clamps attached to his sweet little breasts, vibrating away to increase the sensation while Nightmare used one of his tentacles to fuck Dreams pussy hard with a large dildo.

"have anything to say, dream?" he asked, amused as Dream moaned loudly. Earning a loud growl from an irate Cross on his knees behind Dream, arms cuffed behind his back. Purple ecto manifested along his skeleton showing the lithe, muscled form with large cock standing at attention. A cock ring nestled snugly behind the knot at it’s base. Ball gagged like Dream was, a large metal color around his neck, enchanted to keep him from being annoying in any way.

The dark demigod chuckled as he lifted a tentacle to pull the ball gag from Dream's mouth. "b-brother aaaaaaaaaaaaaaaaaaahhhhhhh-" he cried as Nightmare slammed the dildo up deep. Arching his back as the fourth tentacle pulled at the chain attached to the clamps to further emphasize the point. His skull dropping forward, panting loudly. Staring at Nightmare with a pleading look.

"you know what you're supposed to do, brother." Nightmare hissed as his blue eye light narrowed, belaying his irritation as he pulled at the chain again. "It’d be in your best interest if you want any relief later..." he murmured, letting the chain go as Dream whimpered again, causing Cross to growl protectively into his ball gag as he wanted nothing more than to protect the ball of sunshine.

Nightmare would have nothing of it as he extended a tentacle to smack Cross hard in the ass, making him whimper lowly. Glaring meaningfully over Dream’s shoulder at him, ignored as his brother shuddered and eventually nodded. Panting loudly as he acquiesed towards the demand. Moving forward on his knees and hands now unbound so he could crawl over to his brother.

Whimpering as the dildo was still moving inside of him when he took Nightmare's cock in hand, running his hand along the length. Showing his obedience by running his tongue up along and swirled it around along the light blue tip. Taking the tip and then some into his mouth, starting to suck and made Nightmare nightmare shiver.

His eye light dimming as he sighed in pleasure, looking over at Cross, who was watching them with absolute wide eyed need. Violet ecto drool leaking out and down his chin as he watched his lover servicing the dark lord. His impressive length dribbling down onto the sheets, straining harder against the cuffs as his slitted eye lights dilated even further from the sight.

Barely paying attention as Dust growled loudly and plunged as deep as he could, cumming deep inside Blue's throat as Horror seemed to continue his endless rut. Watching as Dust spent himself entirely before pulling out. Ecto disappeared as he sat back on his ass. Watching unfocused as their Blue whimpered, swallowing.

Not expecting Horror to turn skull upward, a large hand held his chin and took his mouth in a deep kiss, uncaring of the taste of Dust's cum in his mouth. Moving harder, deeper inside of Blue. Increasing his erotic cries as he was fucked, taken by the dark hunter.

While Killer had pulled out of their human, turning her over on her back as he moved over her and plunged right back in to take her hard against the mattress. Tilting her head, kissing her deeply as he continued on having Nightmare's consort in such bliss. She kissed him back, though he suddenly broke it and dipped his head down to take one of her breasts into his mouth and sucked hard on it. Causing her to utter a cry and run her nails down the bone of his shoulders, a shudder ran along his shoulders.

Prompting Nightmare to growl, a dark hand on the back of his brother's skull and pushed Dream’s head further down on his cock. Dream emmited a muffled protest, but took him deeper in to obey as Nightmare continued plunging the dildo in hard. Using his tentacles to spread his legs wider and pull up his lower end to make Cross see everything to drive him even further into the state he wanted to see. However it made him pull at his hold harder, trying to move with all of his strength.

"dust..." Nightmare murmured, getting the assassins attention. "give cross some relief by eating his ass out." he said, getting a wide grin from Dust who turned and moved over towards the warrior. Pushing Cross a bit to bend over slightly, encouraging him to spread his legs a bit wider. Hands moving and rubbing along the cheeks, slowly spreading them apart. Running his burgundy tongue up along the hole, making Cross shudder and strain more.

Dust chuckled against the hole. "bone appetite." he murmured and plunged his tongue in. Sucking along the pucker and slowly working him, Cross shuddered and moaned loudly against the ball gag, the slits in his sockets fuzzed over and rolled up into his sockets. Starting to relax, shivers running up his spine as pleasure coursed through him.

Nightmare grinned again as his control returned in place over the glitched warrior, watching as Killer slammed in and came within his woman with a loud cry. Cumming inside her, with her cumming hard moments after as she arched up into his right hand as his skull rose, kissing her deeply once again. Both panting loudly as he heard a soft cry being uttered from the other end of the bed.

Turning his gaze to the other end of the bed, propped up against a bunch of pillows was none other than a very naked Ink.

Rainbow ecto on full display for everyone to see. Legs draw in and tied up with silk cords so it'd remain that way, spread open to see the large enchanted dildo thrusting deep in his pussy. Another smaller one vibrating hard in his asshole. Nipple clamps attached to his breasts also vibrating, attached to a chain. A ball gag in his mouth as his eyes were fuzzy in this state.

Arms restrained behind his back while propped up there. Watching as Killer eventually moved, lifting their human up into his arms and moving her back over towards their lord and master. He laid back by Nightmare. Holding her close, rubbing her wrists with a bit of healing magic and pulling a blanket around them both as she'd pretty much passed out from all the fucking.

Nightmare reached over to gently run his claws through her hair, she smiled softly as she curled up further into Killer. While the hunter had picked up Blue, sitting back on his coccyx while holding him by the waist. Moving the smaller skeleton, having him ride on his large crimson cock while emitting those sweet erotic sounds as he was fucked. A too wide grin on his face, staring down at Blue with a dilated crimson eye.

Keeping his other hand on his brother’s skull, having him deep throat his cock, who was now so entirely distracted with his task. Eliciting a quiet moan from the dark lord, panting as he began to enjoy what his cute brother was doing. But they needed to start the next act if they were going to be done at a reasonable time.

"dust..." Nightmare said, knowing the assassin was paying attention. "take a break. i'm moving this to the next phase." he said in a firm tone. Dust pulled his tongue out, amused to move and see Cross so out of it at this point. He was more receptive, open and so close to falling into the rut. Panting hard and slumped over, brokenly staring at them with a heated stare of a predator.


	2. Two

**Summary for the Chapter:**

> The conclusion.

Dust scuttled back as Nightmare looked Cross in the sockets, who noticed and tensed up. Growling loudly, so much drool dripping from the ball gag as he prepared for a fight.

"so cross..." the dark demi god began. "dream is sucking my cock really good, likely he practiced on you right?" Cross's eyelights slitted.

"i'm guessing he worked you up good before you grabbed and pinned him down. rut him hard and make him cry-" he slammed the dildo in deep, jolting Dream and making him moan loudly, muffled around his cock.

"-like that." he purred as he slammed the dildo in once more, further sending his brother up into a pleasured haze before pulling it out and making the golden deity whimper in protest.

Tentacles wound around, moving Dreams hips. Raising his lusicous ass up in the air, spreading the cheeks apart and showing a very wet, very ready pussy to the warior. "so since you've been a reasonably good boy. i'll let you fuck him." Cross whimpered. "or i could fuck him-" he said as he let the blue magic holding Cross go. The cock ring disappeared.

Cross snarled into the ball gag and lunged forward, faster than they expected. Without the use of his arms mounted Dream and slammed his cock deep inside, fucking him savagely as he spat out the ball gag off to the side. Biting deep into Dream's shoulder and pushing his lover forward, deep throating him on Nightmare's cock. Making the dark lord moan loudly.

He wrapped his claws around Dream’s skull and thrusts up into his face, holding onto him as he began using his mouth as plesure overrode his thoughts. “oooooooooooo…” taking a bit of time to enjoy the hot little mouth around his cock. “...fuck brother…” shuddering as his eye like drifted upward, he and Cross coming up with a nice momentum as they fucked Dream between them for some time.

Nightmare panted, looking at Ink with a heated blue eye as the interdimensional skeleton moved his hips, juices dripping from his pussy all over his thighs and onto the sheets. A cock ring nestled snugly around the cock, vibrating. "heh...you're next ink..." he purred as he decided enough was enough.

His tentacles coming to life, wrapping around Cross and with some force sent him flying over to another part of bed. Pulling Dream off of his back, pushing him onto his back as his tentacles turned him to better face Cross.

"Wha-" fully in rut, Cross was over him. Slamming his cock inside, he resumed nailing him hard on the mattress. "CROSS!" Dream cried. "Wait-aaaahhhh-please!" he begged as his lover pistoned within and likely drove any semblance of thought from his mind.

The dark lord chuckled as Cross broke what bound his hands, grabbing Dream’s wrists and pinning both above his head with one hand. Clacking teeth as he kissed him, tongues twining together as they became lost in their own world. Grabbing one of his lower thighs to hold the lord of light more easier beneath him while they fucked.

To Nightmare's delight Cross seemed heated enough to hopefully ensure the success of things tonight. "make sure to breed him, cross." he quietly ordered, getting an affirmative growl in reply as he shifted his hips in order to hit a spot in Dream that really got him going. The cries from the lighter deity increased in fervor. "knotting him will keep him bound to you."

He added as an afterthought when glancing over towards Blue and Horror, the hunter having moved his mate on all fours and mounted him. The smaller Sans continuing to utter such sweet cries as Horror drove hard into him, over him. An arm around his middle and holding one of his breasts, crimson eye light rolling up as Blue eventually seemed to arc and cum. His pussy clenched tight, prompting Horror’s normally legendary endurance to short circuit and hit in home until he came, filling him up.

They'd be wrapping it up soon it seemed. In a way similar as Killer holding his mate in his arms, who fell asleep after being cared for and content with everything. All said and good except for Cross who was still wrecking the fuck out of Dream. Leaving nothing more than his sweet treat propped up at the end of the bed who was trying so hard to seem irritated, but couldn't.

He ran his light blue tongue over his teeth as he got up from his spot and crawled across the massive bed over to Ink, sitting before him. "all trussed up and waiting for me-" he murmured as he took the handle of the dildo vibrating away in Ink's well worked pussy. "how cute!" he said as he slammed it up into him. Making him cry and arch his back, skull dropping back back as his sockets widened from the increased pleasure shooting up his spine.

Nightmare couldn't help doing it again, watching the skeleton usually so composed being utterly shattered by this alone. "not so tough without your tools, eh?"

Nightmare kept doing it for some time until he decided enough was enough. His cock was so hard at this point, freely leaking magic all over the sheets, letting out harsh puffs of air through his teeth.

He pulled the dildo out of his pussy, dropping it aside and called forth another tentacle to pull the other out of his ass. "you've come here out of curiosity..." he lengthened his tentacles, using all four to wrap around Inks limbs and lifted him up.

Moving him over towards the other end of the bed where he'd been previously, over by the mass of pillows set up to recline, near over by Killer and his slumbering mate. Killer's sockets peeked open, grinning some as Nightmare ensured Ink would be comfortable where he was. "following dream, who thought the little blueberry was in danger from us..." a grin overtaking his skull. “when he’d actually fell in love and mated Horror…”

He chuckled, running a tentacle along Ink's weeping pussy, eliciting a shiver. "interested in my new mate-who is able to carry my offspring without any issue..." his own cock flashed, glowing a luminous bright blue as he moved closer. Running his long tongue over his cheek, panting and puffing hot air. Ink continuing to shiver.

He leaned over the aspect of creation, rubbing his length over his pussy. "so i'm going to give you a nice little reward..." he lined his cock up, thrusting to penetrate and slowly push his way into him. Making Ink mewl as he tensed and shuddered, the lights in his sockets fuzzy. "an answer you've been seeking. a thought for you to ponder..." he purred as he pressed all the way in.

Licking his teeth. "and when error sees the end result-he'll seethe with jealousy and finally realize what he should've done so long ago..." he thrust deep, starting up a rhythm much more even and less rambunctious then what Cross was doing to Dream, who'd given in and held onto his wild lover for dear life as they fucked.

Another dark chuckle as he moved inside, seeing Ink's face contort in pleasure. Killer seemed to enjoy watching the spectacle with a sort of glee. Everything slowly falling into place at this rate.

By now Horror had taken his place at the end of the bed, having a tired Blueberry in his arms and cuddling him. Entranced as he felt along the smaller Sans swollen belly where the souling grew, not evening paying attention to what was happening. That was fine, really. The two of them were content and what was enough for him.

Killer was also content with her in his arms, watching as he moved hard in Ink as a tentacle yanked at the chain attached to the nipple clamps on Ink's breasts. Making him cry loudly into the ball gag as he continued showing him his power in an entirely different way.

This was absolute bliss. Pure and absolute wonder in the sense as those among his closest and beloved, some his enemy would have the chance to explore their lust in a way that fed him the most. Nothing better as he stopped, picking Ink up again and carrying him over near where Cross continued nailing his brother.

Wild beyond abandonment. No holds barred and showing Dream just what it meant to come dropping in without any real help, or scouting head for the traps he laid in wait. Or the fact he got Cross back with some vague thoughts of family. All in the palm of his hand per say, for now.

He pulled at the cords on Inks legs after laying him down and tossed them aside. letting both limbs free as he rubbed along them, working out the friction from the cords before holding them open at the knee. Growling as he entered Ink again, taking him harder this time. Panting loudly, eye light rolling up into his head.

"fuck ink..." he purred. "so tight." he panted as he was growing closer than he thought he would. Seems Dream practiced real good with Cross. "mmmmmmmmmmm...!"

He pulled the ball gag from Ink's face, letting him finally breathe. Hands on either side of his skull as he kissed him deeply, running his tongue along his, Ink reciprocating as lust addled him entirely at this point. His for the taking, literally and figuratively. It wouldn't be long now, he knew.

He moved Inks legs, placing them over his shoulders to move him entirely into a mating press. Allowing himself to give in to lust as he increased his pace into a punishing rhythm. Growling lightly as he twined and moved his blue tongue along with Inks rainbow one in a desperate need to claim him.

The sounds of his brother and Cross as they mated desperately nearby with how tight Ink was around him was swiftly pushing him towards the edge. A cliff he was about to fall over, taking the plunge in something he wasn't entirely sure of. But he knew this, Ink would be his. Error would be his by proxy. Dream would be out of commission as Cross's intensity would orbit him close into obedience for a time.

The very thought was his undoing as he turned his head and moaned loud and dark in Ink's ear. "oooooooooooooohhhh..." he said as he drove home. Plunging in deep, a shudder running across his shoulders and down his back. Giving in to the great abyss of absolute bliss having his bones rattling so hard it echoed throughout the room.

From his very soul came a distinct ball of his essence. Forming and traveling down through his cock and right into Ink's pussy. An egg of sorts, cumming right after and filling the demi god of creation right up with his seed. Shuddering as his eye flashed, lost as his mind dulled into a pleasure fueled haze. Slamming his knot home, blooming inside a whimpering Ink.

It took a while to return to himself. As he did he heard Cross release a loud snarl as he finished off within his brother. Dream emitting a loud moan as he came hard not long after, being filled with Cross's cum. Shuddering as his head dropped back into the bed, golden eye lights rolling up as Cross laid on top, pushing his knot in him. Locking them together as well.

Nightmare sighed as he wrapped an arm around Ink, rolling them so they were on their sides. Nuzzling his tattooed temple as he distantly deliberated on finding a way for him to have a soul, or to create one from Ink's experience and some help from magic.

Shouldn't be too hard. Just take some time and a bit of ingenuity from some Au's who'd have a few leads. Give Ink a bit of a gift, a means to bring contentment, since he planned to keep him, after all.


End file.
